US3232254A - Stoker - Google Patents

Stoker Download PDF

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Publication number
US3232254A
US3232254A US404073A US40407364A US3232254A US 3232254 A US3232254 A US 3232254A US 404073 A US404073 A US 404073A US 40407364 A US40407364 A US 40407364A US 3232254 A US3232254 A US 3232254A
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Prior art keywords
wall
horizontal surface
grate
stoker
plate
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Expired - Lifetime
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US404073A
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Russell C Rivers
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Riley Power Inc
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Riley Power Inc
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Priority claimed from US95667A external-priority patent/US3169498A/en
Application filed by Riley Power Inc filed Critical Riley Power Inc
Priority to US404073A priority Critical patent/US3232254A/en
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Assigned to ASHLAND TECHNOLOGY, INC., A CORP. OF DE. reassignment ASHLAND TECHNOLOGY, INC., A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: UNITED STATES RILEY CORPORATION, A CORP. OF DE.
Assigned to RILEY STOKER CORPORATION, A MA CORP. reassignment RILEY STOKER CORPORATION, A MA CORP. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: ATEC, INC.
Assigned to ATEC, INC. reassignment ATEC, INC. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: ASHLAND TECHNOLOGY, INC.
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23HGRATES; CLEANING OR RAKING GRATES
    • F23H11/00Travelling-grates

Definitions

  • This invention relates to a stoker and, more particularly, to apparatus arranged to burn fuel on a traveling grate.
  • Another object of this invention is the provision of a stoker of a simple rugged construction which is capable of burning diflicult fuels and which minimizes the possibility of breakage or stoppage of the apparatus due to the nature of unsual objects contained in the refuse.
  • a further object of the present invention is the provision of a traveling grate st-oker having a novel means of preventing material from wedging between the edges of a grate and the adjacent walls.
  • FIG. 1 is a vertical sectional view of an incinerator incorporating the principles of the present invention
  • FIG. 2 is a perspective View of a portion of the invention
  • FIG. 3 is a horizontal sectional view of the invention taken on the line IIIIIl of FIG. 4;
  • FIG. 4 is a vertical sectional view of the apparatus taken on the line IV--IV of FIG. 3.
  • the stoker indicated generally by the reference numeral 10, is shown as consisting of a furnace 11 and a grate 12.
  • the furnace is provided with a hopper 13 into which fuel, such as refuse and garbage, is dumped and a chute 14 extends downwardly therefrom toward the grate 12.
  • the furnace is provided with a roof 15 and a floor 16 joined by side walls 17 and 18, the walls defining a combustion chamber 19 at the bottom of which lies the grate 12.
  • an ash pit 21 At the end of the combustion chamber opposite the chute 14 is an ash pit 21 into which the [grate discharges.
  • a fire wall 22 over which Patented Feb. 1, 1966 gas passes on its way to astack (not shown).
  • the grate 12 consists of a conditioning section 23 and a burning section 24 both of which are chain grates.
  • the burning section underlies the combustion chamber 19 and rests on the floor 16, while the conditioning section 23 underlies the chute 14 at one end and its other end extends downwardly adjacent the upper surface of the burning section.
  • the upper. end of the conditioning section 23 rests on a supporting structure 25 and from this end extends a dust hopper 26.
  • the conditioning section rests on an aubtment 27 extending upwardly from the end of the burning section 24.
  • Three channel beams 28 extend across the conditioning section 23 and divide it into a number of air zones each of which is provided with a damper 29.
  • the burning section 24 is provided with deep I-channels 31 dividing the space between the upper and lower runs of the chain grate into a series of zones each of which is provided with its own. damper 32.
  • the conditioning section 23 is provided with an endless grate 33 which extends around idler sprockets 34 at one end and driven sprockets 35 at the other end.
  • the burning section 24 is provided with an endless grate 36 which extends around idler sprockets 37 at one end and driven sprockets 38 at the other end.
  • FIG. 2 shows a perspective view of the burning section 24, it can be seen that the apparatus is provided with steel side walls 39 and 41 between which the endless grate 36 lies. At one end of the wall 39 is mounted a bearing 42 carrying the shaft on which is mounted the driven sprockets 38, while at the other end the wall sup-ports a bearing 43 and the shaft associated with the idler sprockets 37. Similar bearings are mounted in the other wall 41.
  • the wall 39 is provided with clean-out doors 44.
  • Mounted on top of the side wall 39 is an abutment 45 having an inclined upper surface 46 on which the conditioning section 23 rests.
  • the side wall 41 is provided with the abutment 27 having an inclined upper surface 48 to carry the lower end of the conditioning section.
  • the wall 41 and the abutment 27 are both constructed as hollow ducts and serve to carry air to the conditioning and burning sections.
  • a seal 49 extends from side to side between the two abutments 45 and 27 and extends vertically between the condi tioning section 23 and the surface of the burning section 24.
  • FIGS. 3 and 4 are shown the details of construction of a ledger plate 71 and a corresponding opposite ledger plate 91 on the other side of the grate.
  • the ledger plate 91 overlies the wall 39 of the apparatus, while the ledger plate 74 overlies the wall 41 which, since it is in the form of a duct, is quite wide. Lying between the wall 39 and the wall 78 is the burning section 24 which, for the purpose of conserving space in the drawing, is almost completely bro-ken away.
  • Overlying the Wall 41 is the wall 17 of the furnace, while the opposite wall 18 overlies the wall 39 and the ledger plate 91.
  • the upper edge of the wall 39 is provided with an angle iron 92 which lies in spaced parallel relationship with the lower surface 93 of the wall 18 of the furnace. Between the upper surface of the angle iron 92 and the lower surface 93 of the wall extend separating members 94 and 95 which are welded to the upper surface of the angle iron 92.
  • the ledger plate 91 is provided with deep slots 96 at the edge which extends into the furnace and is provided at its rearward portion with notches 97 and 98 by which it is drawn back against the separating members 94 and 95.
  • a plate 99 extends between the outer ends of the separating members 94 and 95 and through the plate extend bolts 191 and 102 whose heads reside in recesses 103 and 104, respectively, in the ledger plate 91.
  • the bolts 101 and 102 will not be pulled up tightly, but will be locked in place to loosely hold the ledger plate so that the ledger plate may lie in the slot in a loose condition and its furnace edge may rest upon the grate rather than be held rigidly relative thereto.
  • the space between the wall 41 of the grate and the wall 17 of the furnace is divided into a number of slots by separating members 105 and 106.
  • the ledger plate 71 is exactly similar to the ledger plate 91 and is provided with slots in its inner edge and notches at its rearward edge which are drawn back against the inner ends of the separating members 105 and 106.
  • Elongated bolts 107 and 108 lie in recesses in the ledger plate 71 and pull it back against the separating members.
  • a plate 109 is fastened across the outer ends of the separating members and the bolts 107 and 108 pass through this plate and are drawn up against it by suitable nuts.
  • a stoker comprising spaced parallel walls having vertical surfaces facing one another, an endless chain, grate clips fastened to the chain to define an upwardly- V 1* facing horizontal surface extending between the :surfaces and movable in a direction parallel thereto, the edges of the horizontal surface residing closely adjacent 'the wall surfaces, horizontal slots defined by spaced, parallel, facing surfaces in the wall just above the horizontal surface, and ledger plates having a thickness substantially less than the distanc separating the facing surfaces of the slots residing loosely in theslot for substantial vertical movement and extending outwardly therefrom to overlie the horizontal surface adjacent the edges, and means holding each plate in a predetermined horizontal position.
  • each ledger plate has bolts connected thereto and'extending through the slot in a direction away from the wall surface for holding and adjusting the position of the ledger plate in the slot.
  • each ledger plate has recesses in its outer edges in which heads of the bolts reside, the outward opening of each slot being closed by a plate, each plate having'apertures through which the bolts extend and against which the nuts on the bolts are pressed.
  • each of the said walls consists of an upper portion and a lower portion which are maintained in vertically-spaced relationship by spacers to define the said horizontal slots.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Incineration Of Waste (AREA)

Description

Feb. 1, 1966 R. c. RIVERS 3,232,254
STOKER Original Filed March 14, 1961 2 Sheets-Sheet 1 INVENTOR. Russell C. Rivers Feb. 1, 1966 R. c. RIVERS 3,232,254
STOKER Original Filed March 14, 1961 2 Sheets-Sheet 2 INVENTOR. Russell C. Rivers United- States Patent 3,232,254 STGKER Russell C. Rivers, Boylston, Mass, assignor to Riley Stoker Corporation, Worcester, Mass, a corporation of Massachusetts Original application Mar. 14, 1961, Ser. No. 95,667, now latent No. 3,169,498, dated Feb. 16, 1965. Divided and th's application Oct. 15, 1964, Ser. No. 404,073 4 Claims. (Cl. 1104tl) This is a divisional application of patent application Serial Number 95,667, filed March. 14, 1961, now Patent No. 3,169,498, issued Feb. 16, 1965.
This invention relates to a stoker and, more particularly, to apparatus arranged to burn fuel on a traveling grate.
It is common practice to dispose of refuse, such as garbage and rubbish, by burning it, and the traveling grate is ideally suited for this purpose because of its self-cleaning function. However, the burning of such material, as Well as other fuels, on a traveling grate presents problems that are not encountered inth burning of ordinary fuel by this method. For instance, the nature of the material that may arrive at an incinerator is not only unpredictable but of wide variety and the grate may be subjected to high mechanical stresses due to heavy objects being dropped upon the grater Furthermore, any number of melt-able materials may reach the grate'and present problems. In the past, difliculty has been experienced with materials dropping between the sides of the grate and the walls of the furnace and thereby clogging the mechanism by a wedging action. These and other diffi'culties experienced with. the prior art devices have been obviated. in a novel manner by the present invention.
It is, there-fore, an outstanding object of the invention to provide a stoker of a novel unitary construction.
Another object of this invention is the provision of a stoker of a simple rugged construction which is capable of burning diflicult fuels and which minimizes the possibility of breakage or stoppage of the apparatus due to the nature of unsual objects contained in the refuse.
A further object of the present invention is the provision of a traveling grate st-oker having a novel means of preventing material from wedging between the edges of a grate and the adjacent walls.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.
The character of the invention, however, may be best understood by reference to one of its structural forms, as illustrated by the accompanying drawings in which:
FIG. 1 is a vertical sectional view of an incinerator incorporating the principles of the present invention;
FIG. 2 is a perspective View of a portion of the invention;
FIG. 3 is a horizontal sectional view of the invention taken on the line IIIIIl of FIG. 4; and
FIG. 4 is a vertical sectional view of the apparatus taken on the line IV--IV of FIG. 3.
Referring first to FIG. 1, which shows the general features of the invention, the stoker, indicated generally by the reference numeral 10, is shown as consisting of a furnace 11 and a grate 12. The furnace is provided with a hopper 13 into which fuel, such as refuse and garbage, is dumped and a chute 14 extends downwardly therefrom toward the grate 12. The furnace is provided with a roof 15 and a floor 16 joined by side walls 17 and 18, the walls defining a combustion chamber 19 at the bottom of which lies the grate 12. At the end of the combustion chamber opposite the chute 14 is an ash pit 21 into which the [grate discharges. At the end of the combustion chamber is arranged a fire wall 22 over which Patented Feb. 1, 1966 gas passes on its way to astack (not shown). The grate 12 consists of a conditioning section 23 and a burning section 24 both of which are chain grates. The burning section underlies the combustion chamber 19 and rests on the floor 16, while the conditioning section 23 underlies the chute 14 at one end and its other end extends downwardly adjacent the upper surface of the burning section. The upper. end of the conditioning section 23 rests on a supporting structure 25 and from this end extends a dust hopper 26. At its other end the conditioning section rests on an aubtment 27 extending upwardly from the end of the burning section 24. Three channel beams 28 extend across the conditioning section 23 and divide it into a number of air zones each of which is provided with a damper 29. In a similar manner the burning section 24 is provided with deep I-channels 31 dividing the space between the upper and lower runs of the chain grate into a series of zones each of which is provided with its own. damper 32. The conditioning section 23 is provided with an endless grate 33 which extends around idler sprockets 34 at one end and driven sprockets 35 at the other end. In a similar manner the burning section 24 isprovided with an endless grate 36 which extends around idler sprockets 37 at one end and driven sprockets 38 at the other end.
Referring now to FIG. 2, which shows a perspective view of the burning section 24, it can be seen that the apparatus is provided with steel side walls 39 and 41 between which the endless grate 36 lies. At one end of the wall 39 is mounted a bearing 42 carrying the shaft on which is mounted the driven sprockets 38, while at the other end the wall sup-ports a bearing 43 and the shaft associated with the idler sprockets 37. Similar bearings are mounted in the other wall 41. The wall 39 is provided with clean-out doors 44. Mounted on top of the side wall 39 is an abutment 45 having an inclined upper surface 46 on which the conditioning section 23 rests. The side wall 41 is provided with the abutment 27 having an inclined upper surface 48 to carry the lower end of the conditioning section. The wall 41 and the abutment 27 are both constructed as hollow ducts and serve to carry air to the conditioning and burning sections. A seal 49 extends from side to side between the two abutments 45 and 27 and extends vertically between the condi tioning section 23 and the surface of the burning section 24.
In FIGS. 3 and 4 are shown the details of construction of a ledger plate 71 and a corresponding opposite ledger plate 91 on the other side of the grate. As is evident in FIG. 4, the ledger plate 91 overlies the wall 39 of the apparatus, while the ledger plate 74 overlies the wall 41 which, since it is in the form of a duct, is quite wide. Lying between the wall 39 and the wall 78 is the burning section 24 which, for the purpose of conserving space in the drawing, is almost completely bro-ken away. Overlying the Wall 41 is the wall 17 of the furnace, while the opposite wall 18 overlies the wall 39 and the ledger plate 91. The upper edge of the wall 39 is provided with an angle iron 92 which lies in spaced parallel relationship with the lower surface 93 of the wall 18 of the furnace. Between the upper surface of the angle iron 92 and the lower surface 93 of the wall extend separating members 94 and 95 which are welded to the upper surface of the angle iron 92. The ledger plate 91 is provided with deep slots 96 at the edge which extends into the furnace and is provided at its rearward portion with notches 97 and 98 by which it is drawn back against the separating members 94 and 95. A plate 99 extends between the outer ends of the separating members 94 and 95 and through the plate extend bolts 191 and 102 whose heads reside in recesses 103 and 104, respectively, in the ledger plate 91. Pulling up on the nuts on the bolts 101 and 102 will pull the ledger plate back against the separating members 94 and 95. It can be seen, then, that the space between the wall 18 and the angle iron 92, particularly between the supporting members 94 and 95, constitutes a horizontal slot in which the ledger plate 91 resides and which it is possible to use in order to adjust or release the ledger plate from the outside of the wall. It is necessary, of course, to remove the ledger plate from the furnace side, but it can be tightened up or loosened from the outside of the furnace. Generally speaking, the bolts 101 and 102 will not be pulled up tightly, but will be locked in place to loosely hold the ledger plate so that the ledger plate may lie in the slot in a loose condition and its furnace edge may rest upon the grate rather than be held rigidly relative thereto. In a similar way, the space between the wall 41 of the grate and the wall 17 of the furnace is divided into a number of slots by separating members 105 and 106. The ledger plate 71 is exactly similar to the ledger plate 91 and is provided with slots in its inner edge and notches at its rearward edge which are drawn back against the inner ends of the separating members 105 and 106. Elongated bolts 107 and 108 lie in recesses in the ledger plate 71 and pull it back against the separating members. A plate 109 is fastened across the outer ends of the separating members and the bolts 107 and 108 pass through this plate and are drawn up against it by suitable nuts.
It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.
The invention having been thus described, what is claimed as new and desired to secure by Letters Patent is:
1. A stoker, comprising spaced parallel walls having vertical surfaces facing one another, an endless chain, grate clips fastened to the chain to define an upwardly- V 1* facing horizontal surface extending between the :surfaces and movable in a direction parallel thereto, the edges of the horizontal surface residing closely adjacent 'the wall surfaces, horizontal slots defined by spaced, parallel, facing surfaces in the wall just above the horizontal surface, and ledger plates having a thickness substantially less than the distanc separating the facing surfaces of the slots residing loosely in theslot for substantial vertical movement and extending outwardly therefrom to overlie the horizontal surface adjacent the edges, and means holding each plate in a predetermined horizontal position.
2. A stoker as recited in claim 1, wherein each ledger plate has bolts connected thereto and'extending through the slot in a direction away from the wall surface for holding and adjusting the position of the ledger plate in the slot.
3. A stoker as recited in claim 2, wherein each ledger plate has recesses in its outer edges in which heads of the bolts reside, the outward opening of each slot being closed by a plate, each plate having'apertures through which the bolts extend and against which the nuts on the bolts are pressed.
4. A stoker as recited in claim 1, wherein each of the said walls consists of an upper portion and a lower portion which are maintained in vertically-spaced relationship by spacers to define the said horizontal slots.
References Cited by the Examiner UNITED STATES PATENTS 787,636 4/1905 Poppenhusen "110-40 1,982,797 12/1934 Denny 11o FOREIGN PATENTS 373,381 4/1923 Germany.
FREDERICK L. MATTESON, R., Primary Examiner. KENNETH W. SPRAGUE, Examiner.

Claims (1)

1. A STOKER, COMPRISING SPCED PARALLEL WALLS HAVING VERTICAL SURFACES FACING ONE ANOTHER, AN ENDLESS CHAIN, GRATE CLIPS FASTENED TO THE CHAIN TO DEFINE AN UPWARDLYFACING HORIZONTAL SURFACE EXTENDING BETWEEN THE SURFACES AND MOVABLE IN A DIRECTION PARALLEL THERETO, THE EDGES OF THE HORIZONTAL SURFACE RESIDING CLOSELY ADJACENT THE WALL SURFACES, IN THE WALL JUST ABOVE THE HORIZONTAL SURFACE, ING SURFACES IN THE WALL JUST ABOVE THE HORIZONTAL SURFACE, AND LEDGER PLATES HAVING A THICKNES SUBSTANTIALLY LESS THAN THE DISTANCE SEPARATING THE FACING SURFACES OF THE SLOTS RESIDING LOOSELY IN THE SLOT FOR SUBSTANTIAL VERTICAL MOVEMENT AND EXTENDING OUTWARDLY THEREFROM TO OVERLIE THE HORIZONTAL SURFACE ADJACENT THE EDGES, AND MEANS HOLDING EACH PLATE IN A PREDETERMINED HORIZONTAL POSITION.
US404073A 1961-03-14 1964-10-15 Stoker Expired - Lifetime US3232254A (en)

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Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US95667A US3169498A (en) 1961-03-14 1961-03-14 Traveling grate incinerator
US404073A US3232254A (en) 1961-03-14 1964-10-15 Stoker

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4321879A (en) * 1978-06-12 1982-03-30 Toivo Auvo As Furnace for consuming solid fuel
US4444538A (en) * 1982-07-12 1984-04-24 Jerry Manley Automatic log feeder
US4539915A (en) * 1983-09-14 1985-09-10 Francis Bouron Automatic feed device for solid fuel boiler, specifically for logs of wood
US4574712A (en) * 1984-08-27 1986-03-11 David Emil J Wood chip burning stoker type furnace

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US787636A (en) * 1904-03-21 1905-04-18 Herman A Poppenhusen Furnace.
DE373381C (en) * 1923-04-11 Johann Matth Roegels Pendulum slag accumulation device for the completion of traveling grids
US1982797A (en) * 1931-08-07 1934-12-04 Detrick M H Co Stoker furnace construction

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE373381C (en) * 1923-04-11 Johann Matth Roegels Pendulum slag accumulation device for the completion of traveling grids
US787636A (en) * 1904-03-21 1905-04-18 Herman A Poppenhusen Furnace.
US1982797A (en) * 1931-08-07 1934-12-04 Detrick M H Co Stoker furnace construction

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4321879A (en) * 1978-06-12 1982-03-30 Toivo Auvo As Furnace for consuming solid fuel
US4444538A (en) * 1982-07-12 1984-04-24 Jerry Manley Automatic log feeder
US4539915A (en) * 1983-09-14 1985-09-10 Francis Bouron Automatic feed device for solid fuel boiler, specifically for logs of wood
US4574712A (en) * 1984-08-27 1986-03-11 David Emil J Wood chip burning stoker type furnace

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Owner name: ASHLAND TECHNOLOGY, INC., NEW YORK, NY, A CORP. OF

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:UNITED STATES RILEY CORPORATION, A CORP. OF DE.;REEL/FRAME:004435/0797

Effective date: 19850709

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Owner name: ATEC, INC.

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Effective date: 19851205

Owner name: RILEY STOKER CORPORATION, WORCESTER, MA A MA CORP.

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:ATEC, INC.;REEL/FRAME:005521/0514

Effective date: 19900928